Chicago's 'Greenest Street in America' Eats Smog

The chemical reaction caused by sunlight and titanium dioxide in the pavement creates cleaner air on a two-mile stretch of Chicago's Cermak Road.

City officials in Chicago have dubbed a two mile stretch of Cermak Road “the greenest street in America.” And it gets this name for many reasons, one of which is a pavement that reportedly reduces air pollution -- the first such use this technology in the U.S.

The street also was upgraded with various green technology as part of a $14 million project to explore how sustainability in infrastructure can help solve larger environmental problems.

"Sustainability is critical for us," Karen Weigert, chief sustainability officer for the city of Chicago, told AFP. "We think of it as a part of quality of life, about economic opportunity in terms of what kinds of jobs we attract and about stewardship of tax dollars."

The pavement used for the top layer of Cermak Road was developed in Italy after the Vatican began searching for a material that would stay white amid the pollution of Rome, Phys.org reported.

So cement manufacturer Italcementi developed a pavement with titanium dioxide to solve the problem. The chemical reaction caused by sunlight and titanium dioxide in the pavement reportedly speeds up the decomposition process, keeping the surface clean. However, it was soon discovered that it wasn’t just the surface of the church being kept clean, but eight feet of air above the structure’s roof was also measuring cleaner.

The project also uses solar-powered street lights and bioswales with drought-resistant plants to withstand hot seasons without the need for more water. The intelligent use of bioswales and landscape elements placed to displace silt and pollution will help the city manage the large volume of stormwater flowing through the city’s sewers. About 60 percent of the project’s construction waste was reportedly recycled, and about 23 percent of the materials used for the project came from recycled things. It is the combination of all these green elements, city officials said, that will make a project like this successful in the long term.

"These infrastructure projects last for 50, 100 years," Project Manager Janet Attarian told Phys.org, "so you can't afford to redo them again when you finally figure them out."